Zapper with wrist straps? Z4ex Extreme???

Just wondering if anyone knows anything about this particular zapper. I have never had or used one. I did once have a tens unit. Are they similar? Can you strap the handles on to your body or do you have to hold them. I like the idea of the wrists straps, but want to know first if anyone else has used them. How does one put them on the abdomen, with tape? How long do you hold them or leave them on the body and how do you know if they are working. What do you feel? How do you know if there is die off? Thanks to anyone who can help me here...... Tweet